Oil-in-water emulsions

ABSTRACT

The present invention relates to oil-in-water emulsions containing 0.001 to 70% by weight of at least one active substance from the group consisting of phosphates, thiophosphates and/or carbamates, 0.001 to 30% by weight of one or more surfactant compounds from the group consisting of ethoxylated fatty amines or of phosphorylated fatty amine ethoxylates, and also, if desired, adjuvants and water to make up 100% by weight.

Numerous aqueous emulsions of agrochemical active substances havealready been disclosed. Such formulations can be prepared, for example,by dissolving the active substances, which are generally insoluble in-water, in organic solvents and adding emulsifiers and adjuvants, theactive substances, emulsifiers and adjuvants being added in quantitiessuch that sufficiently stable emulsions are formed when the compositionsare formulated with water to the application concentrations.

The prior art has disclosed oil-in-water emulsions which containphosphorylated surfactants.

EP-A-0 224 846 describes plant protection agents based on aqueousemulsions which contain the active substance and, as dispersant, analpha- and omega-phosphorylated ethylene oxide/propylene oxide/ethyleneoxide block copolymer or a salt thereof.

A disadvantage of the emulsions described is that they are onlysubstantially free of water-immiscible organic solvents.

EP-A-0 118 759 discloses plant protection agents in the form of aqueousemulsion concentrates which contain one or more liquid or dissolvedactive substances, water and, as oil- and water-soluble dispersants,from 0.5 to 20% by weight of salts of phosphorylated block copolymersbased on propylene oxide and ethylene oxide, of the formula ##STR1## inwhich r and s independently of one another are a number between 20 and300,

t is a number between 10 and 300,

n and m independently of one another are 1 or 2, the sum n+m necessarilybeing 3, and

M is an alkali metal cation, one equivalent of an alkaline earth metalcation, ammonium, alkylammonium or alkanolammonium.

The only active substances which are mentioned as being suitable arehydrolysis-resistant insecticides, herbicides and pheromones.

U.S. Pat. No. 4,107,302 relates to aqueous insecticide concentratemixtures which contain an active substance from the group consisting ofphosphates and/or thiophosphates, and a surface-active compound. Asnonionic surface-active compounds, ethoxylated alkylallylphenyl ethersare preferably employed, for example distyrylmethylphenol ethoxylatewith 10 EO. A disadvantage of the mixtures described therein is the needto use an aqueous buffer solution in order to establish a pH range offrom 3.0 to 8.5. Moreover, the addition of organic solvents such asketones, ethers and alcohols is recommended for mixtures whose contentof active substance exceeds 30% by weight.

EP-A-0 196 469 relates to phosphate-containing macro-emulsions where thesurfactant employed to disperse the active substance is the aqueoussolution of a nonylphenol-propylene oxide-ethylene oxide adduct and/orthe aqueous solution of an ethylene oxide/propylene oxide/ethylene oxideblock copolymer having an average molecular weight of between 2000 and8000 and HLB values of between 8 and 30. The macroemulsions describednecessarily contain glycerol as adjuvant. When employing an activesubstance which is solid at room temperature, a solution of thesubstance concerned in an aromatic diluent is used.

EP-A-0 130 370 relates to plant protection agent combinations which areobtained by mixing a dispersion of active substance and a solution ofactive substance. The plant protection agent combinations prepared inthis way contain as phosphorylated surfactants, for example, the Na saltof C₁₂ -C₁₈ -alkyl polyglycol ether phosphate mono/diester (®Forlanit P,Henkel KGaA) and triethanolamide salts of a mixture of mono- anddiphosylates of a tri-styrylphenol polyglycol ether having 18 EO units(®Soprophor FI, Rhone-Poulenc) and, as sulfated and sulfonatedsurfactant compounds, for example, the Na salt of the sulfosuccinicmonoester and Na ligninsulfonate. A disadvantage of the plant protectionagent combinations described therein is the use of solutions of activesubstances, which have a high content (from 40 to 48% by weight) oforganic solvents such as xylene and methylnaphthalene.

Oil-in-water emulsions which contain nonionic surfactants as dispersantsare likewise known from the prior art.

EP-A-0 289 909 relates to stable aqueous emulsions of organophosphoruspesticides which in addition to the active substance contain a nonionicblock copolymer, copolymer or coblock copolymer as surfactant and also,necessarily, urea, so as to achieve an adequate degree of phasestabilization.

The object of the present invention was to provide plant protectionformulations, in the form of aqueous emulsion concentrates based onactive substances, especially of active substances which are sensitiveto hydrolysis, from the group consisting of phosphates, thiophosphatesand/or carbamates, which formulations are completely free from organicsolvents, have an excellent chemical and physical stability, areresistant in particular to hydrolysis, and are also stable at lowtemperatures (-10° C.), and which are dilutable with water as desiredeither alone or in a mixture with other liquid formulations.

It has now surprisingly been found that the use of specific surfactantcompounds leads to the desired plant protection formulations.Specifically, these surfactant compounds are

A) fatty amine ethoxylates of the formula I and

B) phosphorylated fatty amine ethoxylates of the formula II.

The present invention relates to oil-in-water emulsions comprising:

0.001 to 70% by weight, preferably 0.5 to 50% by weight, of at least oneactive substance from the group consisting of phosphates, thiophosphatesand/or carbamates,

0.001 to 30% by weight, preferably 0.1 to 20% by weight, of one or moresurfactant compounds from the group consisting of

A) ethoxylated fatty amines of the formula I ##STR2## in which R¹ ishydrogen

C₁ -C₂₄ -alkyl,

C₂ -C₂₄ -alkenyl,

C₂ -C₂₄ -alkynyl,

C₅ -C₂₄ -cycloalkyl,

C₆ -C₃₆ -aryl,

C₆ -C₄₈ -alkaryl,

C₆ -C₃₆ -heteroaryl or

C₆ -C₄₈ -heteroalkaryl,

R² is R¹, with the exception of hydrogen, or is a group of the formula(CH₂ --CH₂ --O)_(y) --H

and

x, y independently of one another are a number between 1 and 200

or

B) phosphorlated fatty amine ethoxylates of the formula II ##STR3## inwhich R¹ is hydrogen

C₁ -C₂₄ -alkyl,

C₂ -C₂₄ -alkenyl,

C₂ -C₂₄ -alkynyl,

C₅ -C₂₄ -cycloalkyl,

C₆ -C₃₆ -aryl,

C₆ -C₄₈ -alkaryl,

C₆ -C₃₆ -heteroaryl or

C₆ -C₄₈ -heteroalkaryl,

R is R¹, with the exception of hydrogen, or is a group of the formula##STR4## R³, R⁴ independently of one another are hydrogen, an alkalimetal cation, one equivalent of an alkaline earth metal ion,

ammonium,

mono-, di- or tri(C₁ -C₁₂ -alkyl)ammonium or

mono-, di- or tri(C₁ -C₁₂ -alkanol)ammonium,

and

x, y independently of one another are a number between 1 and 200

and, if desired, adjuvants and

water to make up 100% by weight.

The O/W emulsions according to the invention contain at least oneagrochemical active substance, an active substance for controllingharmful organisms in the household and hygiene sector and/or apharmacologically active substance from the class of the phosphates,thiophosphates and/or carbamates. In this context the active substances,preferably active substances sensitive to hydrolysis, which are suitableinclude both those substances which are liquid at room temperature andthose which are solid at room temperature. Such active substances areknown and described, for example, in "The Pesticide Manual" 9th edition,The British Crop. Protection Council, 1991.

In the present case the term agrochemical substances is understood torefer to those substances which are usually employed in plantprotection. Examples of these include insecticides, acaricides,fungicides, nematicides, herbicides, molluscicides, rodenticides, growthregulators, safeners, adjuvants, fertilizers and algicides.

Specific examples of such active substances are:

O,O-diethyl O- 2-isopropyl-4-methyl-6-pyrimidyl! thiophosphate(diazinon)

O,O-diethyl O- 3,5,6-trichloro-2-pyridyl!thiophosphate (chlorpyrophos)

2-(1-methylpropyl)phenyl methyl carbamate (BPMC)

O,O-dimethyl S-methylcarbamoylmethyl thiophosphate (dimethoate)

chlorobicyclo 3.2.0!hepta-2,6-diene-6-yl phosphate (heptenophos)

O,O-diethyl O-1-phenyl-1H-1,2,4-triazol-3-yl thiophosphate (triazophos)

ethyl 2-diethoxyphosphinothioyloxy-5-methylpyrazolyl1,5-α!pyrimidine-6-carboxylate (pyrazophos)

O,O-diethyl O-(4-nitrophenyl) thionophosphate

O,O-dimethyl O-(4-nitrophenyl) thionophosphate (fenitrothion)

O-ethyl O-4-methylthiophenyl S-propyl dithiophosphate

2-isopropoxyphenyl N-methylcarbamate

2,3-dihydro-2,2-dimethyl-7-benzofuryl methylcarbamate

3,5-dimethyl-4-methylthiophenyl N-methylcarbamate

O,O-diethyl O-(3-chloro-4-methyl-7-coumarinyl) thibphosphate

S- 1,2-bis (ethoxycarbonyl) ethyl! O,O-dimethyl dithiophosphate(malathion)

O,O-dimethyl O-4-methylmercapto-3-methylphenyl thionophosphate(fenthion, Lebaycid)

O-ethyl O-2-isopropyloxycarbonylphenyl N-isopropylthionophosphoramide.

In the present case, active substances for controlling pests in thehousehold and hygiene sector are to be understood as all conventionalactive substances of low solubility in water. Specific examples of suchactive substances are:

2-isopropoxyphenyl N-methylcarbamate

O,O-diethyl O-4-nitrophenyl thionophosphate (ethylparathion)

O,O-dimethyl O-4-nitrophenyl thionophosphate (methylparathion)

S- 1,2-bis (ethoxycarbonyl) ethyl! O,O-dimethyl dithiophosphate

O,O-dimethyl O-3-methyl-4-nitrophenyl thionophosphate (sumithion,folithion)

O,O-dimethyl O-4-methylmercapto-3-methylphenyl thionophosphate(Lebaycid, fenthion).

In the present case pharmacologically active substances are to beunderstood as substances of low solubility in water which can bepreferably employed in the veterinary sector. An example of such activesubstances is chlorobicyclo 3.2.0!hepta-2,6-dien-6-ylphosphate(heptenophos).

The formulations according to the invention contain at least onecompound of the formula I or II.

In the compounds of the formula I R¹ is preferably hydrogen, C₁₀ -C₁₈-alkyl, C₂ -C₁₈ -alkenyl, C₆ -C₂₀ -cycloalkyl, C₆ -C₁₈ -aryl or (C₁ -C₁₂-alkyl)₃ -phenyl, especially C₁ -C₁₂ -alkylphenyl or mono-, di- ortristyrylphenyl.

R² is preferably C₁₀ -C₁₈ -alkyl, C₂ -C₁₈ -alkenyl, C₆ -C₂₀ -cycloalkyl,C₆ -C₁₈ -aryl, (C₁ -C₁₂ -alkyl)₃ -phenyl, and in particular C₁ -C₁₂-phenyl, mono-, di- or tristyrylphenyl or a group of the formula (CH₂--CH₂ --O)_(y) --H in which y is a number between 1 and 120.

Since the amines which are employed in the synthesis of the compounds ofthe formula. I, especially in the case of fatty amines in which R¹and/or R² are alkyl and/or alkenyl groups, generally represent randommixtures of homologs and isomers, it is advantageous to talk of anaverage number of carbon atoms for these radicals R¹ and R².

Where they are not hydrogen, the radicals R¹ and R² may carry suitablesubstituents, examples being halogen atoms, alkoxy group, hydroxylgroup, nitro group, amino group and/or carboxyl ester group.

The indices x and y indicate the number of moles of ethylene oxideunits. The preferred ranges for x and y are between 1 and 120, between 1and 80 and between 1 and 30.

Quite particularly suitable fatty amine ethoxylates of the formula I arecoconut fatty amine ethoxylates, oleylamine ethoxylates, stearylamineethoxylates and tallow fatty amine ethoxylates in which x is a numberbetween 1 and 40 and the corresponding bisethoxylates thereof in which xand y independently of one another are a number between 1 and 40.

The surfactants of the formula I can be prepared in a simple manner.Usually these compounds are prepared by ethoxylation of the amines onwhich they are based (see K. Kosswig and H. Stache, "Die Tenside" TheSurfactants!, Hauser-Verlag, p. 157).

For the compounds of the formula II R¹ is preferably C₁₀ -C₁₈ -alkyl, C₂-C₁₈ -alkenyl, C₆ -C₂₀ -aryl, C₁ -C₁₂ -alkylphenyl, or mono-, di- ortristyrylphenyl.

R² is preferably C₁₀ -C₁₈ -alkyl, C₂ -C₁₈ -alkenyl, C₆ -C₂₀ -aryl, C₁-C₁₂ -alkylphenyl, mono-, di- or tristyrylphenyl or a group of theformula ##STR5## in which y, R³ and R⁴ have the preferred meaningsindicated below.

Since the amines which are employed in the synthesis of the compounds ofthe formula II, especially in the case of fatty amines in which R¹and/or R² are alkyl and/or alkenyl groups, generally represent randommixtures of homologs and isomers, it is advantageous to talk of anaverage number of carbon atoms for these radicals R¹ and R².

Where the radicals R¹ and R² are other than hydrogen, they may carrysuitable substituents, examples being halogen atoms, alkoxy groups,hydroxyl groups, nitro groups, amino groups and/or carboxyl estergroups.

For the indices x and y the preferred ranges are between 1 and 120,between 1 and 80 and between 1 and 30. R³ and R⁴ independently of oneanother are preferably hydrogen, an alkali metal ion, mono-, di- ortri(C₂ -C₄ -alkyl)ammonium or tri(C₂ -C₄ -alkanol)ammonium.

The surfactants of the formula II can be prepared in a simple manner.Usually these compounds are produced by reaction of the amineethoxylates on which they are based with polyphosphoric acid orphosphorus pentoxide (see K. Kosswig, loc. cit., p. 133).

The O/W emulsions according to the invention contain water as continuousphase. In the case of concentrated emulsions the proportion of water isrelatively low, whereas the emulsions in the diluted state containrelatively large quantities of water. The oil phase (=disperse phase) ispresent in the form of finely divided droplets in the aqueous phase, thedroplet size being variable within a certain range. The particlediameter is generally between 0.001 and 10 μm, preferably between 0.01and 5 μm.

These O/W emulsions advantageously contain no organic solvents.Therefore they have a high flash point, are of low flammability and arevirtually odorless.

Adjuvants which may be present in the oil-in-water emulsions accordingto the invention are preservatives, low temperature stabilizers, dyesand odor improvers. Examples of preservatives are 2-hydroxybiphenyl,sorbic acid, p-hydroxybenzaldehyde, methyl p-hydroxybenzoate,benzaldehyde, benzoic acid, propyl p-hydroxybenzoate and p-nitrophenol.The content of preservative in the emulsion may be between 0.01 and 1%by weight.

Suitable low temperature stabilizers are glycol, glycerol, polyethyleneglycol, sugars and salts such as ammonium sulfate and sodium oleate, theemulsions usually being able to have a content of from 1 to 10% byweight. Examples of dyes are azo dyes and phthalocyanine dyes. Odorimprovers which it is possible to employ are perfume oils.

One example of a suitable preparation process for these O/W emulsions isdescribed in EP-B-0 130 370. In principle, however, the two phases canbe brought into the desired state by stirring.

The oil-in-water emulsions are distinguished by the fact that they arestable under the conditions prevailing in practice. On long-term storagethese emulsions remain unchanged with regard to their physical stabilityand their content of active substance both at high temperatures (50° C.)and at low temperatures (-5° C., -10° C.). A further advantage is thatactive substances which are solid or liquid at room temperature can beemulsified with equal success. The mandatory addition of glycerol and oforganic solvents, especially when solid active substances are employed(cf. EP-A-0 196 463), is not required.

The oil-in-water emulsions according to the invention can be appliedeither as prepared or after dilution beforehand. In this context theirapplication depends on the concentration of the oil-in-water emulsionand on the particular indication. The emulsion is applied by theconventional methods and thus, for example, by spraying or pouring. Inthe application of the oil-in-water emulsions according to the inventionan excellent activity was found with regard to harmful organisms such asaphids, grain weevils, mealy-bugs and bean weevils. In this context itshould be mentioned that no phytotoxicity was detected, especially inrelation to dwarf beans, field beans, tomatoes, cucumbers, wild applestock and vines.

EXAMPLES

Plant Protection Formulations With Surfactant of the Formula I

Table I shows oil-in-water emulsions according to the invention whichcontain as surfactant compound a bisethoxylated tallow-fatty amine (R¹=C₁₄ (5%), C₁₆ (30%), C₁₈ (65%)., x=7, y=8).

The emulsions indicated are stable on storage for a period of at leastone month (storage temperature: 25° C., 50° C.).

                  TABLE I    ______________________________________    Data in % by weight, water to make up to 100% by weight    Example    1      2      3    4    5     6    7    ______________________________________    Surfactant 7.0    7.0    6.0  7.0  8.5   5    7.0    Malathion  42.0   40.0   35.0 42   42    30   42    Lactic acid               0.35   0.34   0.3  0.35 0.42  0.25 0.35    Kelzan, 2% in H.sub.2 O               13.3   13.3   13.3 9.4  10.0  18.0 2.0    ______________________________________

Plant Protection Formulations With Surfactant of the Formula II

Table II shows oil-in-water emulsions according to the invention whichcontain a phosphorylated fatty amine bisethoxylate of the formula II

in which

R¹ is C₁₄ (5%), C₁₆ (30%), C₁₈ (65%)

R² is a group of the formula ##STR6## in which R³ and R⁴ are hydrogen,

x is the number 7 and

y is the number 8.

    ______________________________________    Data in % by weight, water to make up to 100% by weight    Example      1        2      3      4    5    ______________________________________    Malathion    42.0     42.0   35.0   25.0 40.0    Surfactant 1 7.0      8.0    6.0    9.0  11.0    Kelzan, 2% in H.sub.2 O                 13.3     15.0   10.8   20.0 17.0    Triethanolamine                 3.6      4.0    3.1    4.7  5.9    ______________________________________

We claim:
 1. An oil-in-water emulsion which contains one or more activesubstances and one surfactant compound, consisting essentially of:0.001to 70% by weight, of at least one active substance from the groupconsisting of phosphates, thiophoshates, carbamates, and mixturesthereof, 0.001 to 30% by weight, of one surfactant compound from thegroup consisting ofA) ethoxylated fatty amines of formula I ##STR7## inwhich R¹ is hydrogenC₁ -C₂₄ -alkyl, C₂ -C₂₄ -alkenyl, C₂ -C₂₄ -alkynyl,C₅ -C₂₄ -cycloalkyl, C₆ -C₃₆ -aryl, C₆ -C₄₈ -alkaryl, C₆ -C₃₆-heteroaryl or C₆ -C₄₈ -heteroalkaryl, R₂ is R¹, with the exception ofhydrogen, or is a group of the formula (CH₂ --CH₂ --O)_(y) --H and x, yindependently of one another are a number between 1 and 200 and B)phosphorylated fatty amine ethoxylates of the formula II ##STR8## inwhich R¹ is hydrogenC₁ -C₂₄ -alkyl, C₂ -C₂₄ -alkenyl, C₂ -C₂₄ -alkynyl,C₅ -C₂₄ -cycloalkyl, C₆ -C₃₆ -aryl, C₆ -C₄₈ -alkaryl, C₆ -C₃₆-heteroaryl or C₆ -C₄₈ -heteroalkaryl, R² is R¹, with the exception ofhydrogen, or is a group of the formula ##STR9## R³, R⁴ independently ofone another are hydrogen, an alkali metal cation, one equivalent of analkaline earth metal ion, ammonium, mono-, di- or tri(C₁ -C₁₂ -alkyl)ammonium or mono-, di- or tri(C₁ -C₁₂ -alkanol) ammonium, and x, yindependently of one another are a number between 1 and 200, but notboth groups A) and B) and, optionally adjuvants and water to make up100% by weight.
 2. An oil-in-water emulsion as claimed in claim 1,wherein in the surfactant compound of the formula IR¹ is hydrogen, C₁₀-C₁₈ -alkyl, C₂ -C₁₈ -alkenyl, C₆ -C₂₀ -cycloalkyl, C₆ -C₁₈ -aryl, or(C₁ -C₁₂)₃ -phenyl.
 3. An oil-in-water emulsion as claimed in claim 1,whereinR² is C₁ -C₁₀ -alkyl, C₂ -C₁₈ -alkenyl, C₆ -C₂₀ -cycloalkyl, C₆-C₁₈ -aryl, (C₁ -C₁₂ -alkyl)₃ -phenyl, C₁ -C₁₂ -alkylphenyl, mono-, di-or tristyrylphenyl or a group of the formula (CH₂ --CH₂ --O)_(y) --H inwhich y is a number between 1 and
 120. 4. An oil-in-water emulsion asclaimed in claim 1, wherein in the surfactant compounds of the formula Ix and y independently of one another are a number between 1 and
 120. 5.An oil-in-water emulsion as claimed in claim 1, wherein in thesurfactant compounds of the formula IIR¹ is C₁₀ -C₁₈ -alkyl, C₂ -C₁₀-alkenyl, C₆ -C₂₀ -aryl, C₁ -C₁₂ -alkylphenyl or mono-, di- ortristyrylphenyl.
 6. An oil-in-water emulsion as claimed in claim 1,wherein in the surfactant compounds of the formula IIR is C₁₀ -C₁₈-alkyl, C₂ -C₁₈ -alkenyl, C₆ -C₂₀ -aryl, C₁ -C₁₂ -alkylphenyl, mono-,di- or tristyrylphenyl or a group of the formula ##STR10## in which R³and R⁴ independently of one another are hydrogen, an alkali metal ion,mono-, di- or tri(C₂ -C₄ -alkyl)ammonium or tri(C₂ -C₄ -alkanol)ammoniumand y is a number between 1 and
 120. 7. An oil-in-water emulsion asclaimed in claim 1, wherein x and y independently of one another are anumber between 1 and
 120. 8. An oil-in-water emulsion as claimed inclaim 1, which comprises as adjuvants preservatives, low temperaturestabilizers, dyes and/or odor improvers.
 9. An oil-in-water emulsion asclaimed in claim 1, wherein the oil phase is present in the form offinely divided droplets in the aqueous phase.
 10. An oil-in-wateremulsion as claimed in claim 1, wherein the particle diameter of thedroplets is between 0.001 and 10 μm.
 11. An oil-in-water emulsion asclaimed in claim 1, wherein said emulsion is essentially free of anyorganic solvent.
 12. A method of protecting plants comprising the stepof applying to the plants the oil-in-water emulsion as claimed inclaim
 1. 13. A method as claimed in claim 12, wherein said methodassists in the control of organisms harmful to the plants.
 14. Anoil-in-water emulsion which contains one or more active substances andone surfactant compound, and comprises0.001 to 70% by weight, of atleast one active substance from the group consisting of phosphates,thiophoshates, carbamates, and mixtures thereof, 0.001 to 30% by weight,of one surfactant compound from the group consisting ofA) ethoxylatedfatty amines of formula I ##STR11## in which R¹ is hydrogenC₁ -C₂₄-alkyl, C₂ -C₂₄ -alkenyl, C₂ -C₂₄ -alkynyl, C₅ -C₂₄ -cycloalkyl, C₆ -C₃₆-aryl, C₆ -C₄₈ -alkaryl, C₆ -C₃₆ -heteroaryl or C₆ -C₄₈ -heteroalkaryl,R² is R¹, with the exception of hydrogen, or is a group of the formula(CH₂ --C₂ --O)_(y) --H and x, y independently of one another are anumber between 1 and 200 and B) phosphorylated fatty amine ethoxylatesof the formula II ##STR12## in which R¹ is hydrogenC₁ -C₂₄ -alkyl, C₂-C₂₄ -alkenyl, C₂ -C₂₄ -alkynyl, C₅ -C₂₄ -cycloalkyl, C₆ -C₃₆ -aryl, C₆-C₄₈ -alkaryl, C₆ -C₃₆ -heteroaryl or C₆ -C₄₈ -heteroalkaryl, R² is R¹,with the exception of hydrogen, or is a group of the formula ##STR13##R³, R⁴ independently of one another are hydrogen, an alkali metalcation, one equivalent of an alkaline earth metal ion, ammonium, mono-,di- or tri(C₁ -C₁₂ -alkyl) ammonium or mono-, di- or tri(C₁ -C₁₂-alkanol) ammonium, and x, y independently of one another are a numberbetween 1 and 200, but not both groups A) and B) and, optionallyadjuvants and water to make up 100% by weightwherein: the amount of saidactive substance is 0.5 to 50% by weight, and the amount of saidsurfactant compound is 0.1 to 20% by weight; in said surfactant compoundof formula I, R¹ is C₁ -C₁₂ -phenyl or mono-, di- or tri-styrylphenyl,and x and y, independently of one another, are numbers between 1 and 80;and the oil phase is present in the form of finely divided droplets inthe aqueous phase, said droplets having a particle diameter between 0.01and 5 μm.
 15. An oil-in-water emulsion as claimed in claim 14, wherein xand y, independently of one another, are numbers between 1 and 30, andwherein said particle diameter is between 0.1 and 2 μm.
 16. Anoil-in-water emulsion as claimed in claim 14, wherein at least one saidactive substance is active in the control of harmful organisms and issensitive to hydrolysis.